/*
   Copyright (c) 2011, 2012 Mizar Tools Contributors (mizartools.org)

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
*/
/*  Contributors :
 *	2011-02-18 Marco Riccardi - initial implementation
 *  2012-04-06 Marco Riccardi - added message in DliParseException
 *
 */
package org.mizartools.dli;

import java.util.LinkedList;

public class Fields {

    private LinkedList<ItemId> itemIdList = new LinkedList<ItemId>();

	public static Fields newInstance(String string) throws DliParseException {
		Fields fields = new Fields();
		if (string.equals("$fields")){
			return fields;
		}
		int position = string.indexOf("(");
		if (position == -1) {
			throw new DliParseException("["+string+"] is not valid in Fields");
		}
		if (!string.substring(0, position).equals("$fields")){
			throw new DliParseException("["+string+"] is not valid in Fields");
		}
		string = string.substring(position+1, string.length()-1);
		int positionComma = Utility.searchSeparationComma(string);
		while (positionComma != -1) {
			fields.itemIdList.add(ItemId.newInstance(string.substring(0, positionComma)));
			string = string.substring(positionComma+1, string.length());
			positionComma = Utility.searchSeparationComma(string);
		}
		fields.itemIdList.add(ItemId.newInstance(string));
		return fields;
	}

	private Fields(){}
	
    public Fields(LinkedList<ItemId> itemIdList) throws DliException {
		if (itemIdList == null){
			throw new DliException();
		}
		this.itemIdList = itemIdList;
    }
	
	@Override
	public String toString() {
		StringBuilder sb = new StringBuilder();
		sb.append("$fields");
		if (itemIdList.size() != 0){
			sb.append("(");
			boolean first = true;
			for (ItemId itemId : itemIdList){
				if (first) first = false;
				else sb.append(",");
				sb.append(itemId.toString());
			}
			sb.append(")");
		}
		return sb.toString();
	}

}
